Telephone system



v| J. sTEvl-:NsoN 1.334,696

Nov. 5, 1929.

TELEPHONE SYSTEM Filed Feb. 24, 1925 s sheets-sheet 1 l l /|l J9 15 \ZOj??? z/ 17\y Jf/ il?. l

l.. J. sTEvENsoN 1,734,696

Nov. 5, 1929.

TELEPHONE SYSTEM I v Filed Feb. 24, 1925 5 sheets-sheet 2 IZ-o 7g 1.1/7f 16"J Patented Nov. 5, 1929 LESTER J'. STEVENSON, OF' CHICAGO, ILLINOISTELEPHONE SYSTEM Application filed February 24., 1925. Serial No.10,997.

y'Ihis invention relates to improvements in telephone systems and has todo more particularly with the handling of calls between an exchangeswitchboard and a plurality of subscribers7 stations connectedtherewith.

The principal object of my invention is to provide an improvedarrangementin-connection with the exchange board whereby a call normallyintended for. any one of the subscribers may'under predeterminedconditions be transferred and handled by an operator designated toattend to such calls, as, for instance, when thesubscriber expects to betemporarily absent from his station and wishes to have messagesdelivered to the calling party or have messages received from thecalling party during his absence.

Other objects of invention will` appear from time to timeas thevdescription proceeds.V

My invention'in its broadest aspect consists in the provisionof apluarlity of circuits auxiliary to the usual subscribers circuits andprovidedwith a manual 'switch and a signal such as a lamp in such amanner that it thev switch is closed the signal will be actuated by thesame instrumentality used in calling the subscriber. In carrying out'myinvention, the signal andswitch may be located either upon the usualswitchboard so that the regular switchboard operato'r'can handle thecall intended for the subscriber, or the signal and switch, togetherwith an answering jack, may be located upon a special switchboard which,for convenience, may be called a tell-tale board, to be handled by aspecial opera-tor, or the manual switchV may be located at one place,as, for instance, vat a supervisors desk, while the signal, to-

gether with an answering jack -may be lo cated on another switchboard tobe hanf dled by a tell-tale operator. The calling dev` vices whichoperate the telltale signal may consist in the usual ringino devices,such as the magneto or selective bell-ringing devices in a manualoperators cord-circuit, or automatic ringing devices. Y

My invention may best be understood by reference to the accompanyingdrawings showing its application lin various ways to switchboards of thecommon battery type. It will be understood to those famliar with theart, however, that it may be similarly applied `to either single ormultiple switch boards of the common-battery, magneto or automatic type.i

In the drawings, f

Figure l shows the arrangement ofl my improved system as applied to anordinary branch exchange switchboard and consists in connecting with theswitchboard a separate tell-tale board havingjaclr circuits in multiplewith the subscribers circuit on the main switchboard, and a remote`control switch` board interposed between the two first named boards forcontrolling the several multiple circuits.

Figure 2 is an electrical wiring diagram showing'one form in which eachof the subscribers circuits may be embodied. In this form a special jackis provided to control thetell-tale circuit t Figure 3 illustratesanother form in which a standard jack of the two wire type is used, butin which a special relay is added to the ordinary switchboard tn operatethe tell-tale circuit.. l

Figure 4: is still another form using a standard double circuit jack,but inwhich another form of relay is used in the tell-tale circuit. Y

y 4Figure 5 is a view showing the arrangement of an ordinary branchexchange switchboard and a tell-tale switchboard similar to Figure 1,but in which the tell-tale switch devices are incorporated in thetell-tale switch board.

Figure 6 is a diagrammatic view illustrat- Vingv a form 0I" circuit inwhich the switchis incorporated on the tell-tale switchboard as shown inFigure 5.

Figure 7 isa view showing one manner in which the tell-tale circuits-may' be incorpcrated in the regular branch exchange switchboarchthisboard being-termed Jfor convenience a double dutyV board.

Figure 8 is a diagrammatic view of one form of circuit which may beemployed in the double-duty board Vshown in` Figure 7.-

Figure 9 is a circuit similar to Figure 8, loo

but in which another arrangement of signals is provided.

Figure is a view showing a switch arrangement applicable to the formsshown in Figures 8, 9, or 10, topermit one audible signal to serve allthe subscribers circuits.

Figure "11 is a view showing another arrangement ol' tell-talev switchesincorporated in the main switchboard with theV tell-tale switch adjacentits correspondingjack.

Figure 12 is another form of circuit in which the tell-tale signal isoperated by being placed in series with the through circuit signal inthe operators cord'circuit.

Figure 13 is a view similar to Fig. 12, but includin'g'ja relay inthetell-*tale circuitto gilve full vol-t-age'on the tell-'talc signal. L

Reierringv now to 'details 'shown in the drawings,'Figure 1 showsV atypical installation of my' invention asapplied to an Ordin# aryexchange switchboard 10,'provided with a plurality .of subscribersjacks11 and associatedsignals 12l in' the usual manner. For conveniencefonlyone 'ofthe jacks'4 and signals are illustrated, it vbeing understood`that the face of the'boar'd is'provi ded with a plu'- rality of similardevices, each'servingone of thesubsc'ribes lines'served by the board.The boardis' also providedv with the usual operatin'gxcord circuits' andoperators equip.-1 ment, including 'listeningin and ringingdevices .andtrunk linev Vconnections,"which` need not be shown or described indetail as they form, 'no' part ofthe present invention? l have'chosen:to show a- 'sign'al device ofthelainp type such as is commonly? usedwith common-,battery switchboards,`but -it will be understood that anyother 'signal device such asthe shutter vtype may beused' with equalfacility.; A 'second board '15", which for con-` venience 1 refer to asthe tell-tale?) board is provided with a plurality of jacks 16 and as-`scciate signals .17 corresponding with the number of subscribers7circuits served by the'k manrswitchboard 10 and each of thecorresponding jacks and signals being connected' by separate circuits,which connection, as illustrated in the forms shown in Figures 2,

, 3, and 4, hereinafter to be described in detail.

1 call a remote control switchboard.

.ing subscribers jacks andtell-tale signals on the two switchboards 10and 15- respective-y ly. Inasmuchv as each of these switches 26 consistof simple contacting devices of any suitable construction, they vmay bemounted in coi'np-act arrangement so that theremote control' board 25 asshown is considerably smaller than the other switchboards 10 and 15.

Referring now to the cir-cuit shown in Figure 2 illustrating the use ofmy invention in connection with the ordinary two-wire common-batterysystem, the subscribers circuit is'shown in the usualdiagrami'natic'form consisting of a transmitter 30,y receiver 31, phoneAcondenser 32, induction coil 33, bell 35, condenser SG-an-d mainsubscribe-rs lines 40 and 41, leading to the subscribers jack indicatedgenerally at 42. rlihe jack is provided with a pair of spring contacts43 and 44 adapted to be engaged by the plug inserted A the'Y relay 54serving toy control the local circuit-containing'the linelarnp 12 andpilot relay 61vwhic`h' relay :in vturn l'controls the local circuitincluding-'fa'pilot lamp'62 of the usual form. f

The equipment *on theV tell-taleboard 15 consists of a simple iack 16having an upper andlower spring contacts 71 and "Z2 connected inmultiple with the subseribers linefin the present instance being`rparallelacrossthe corresponding spring lcontacts 43' and'44 ofthe'mai'n switchboard jack 42. The Jsignaly device 17of'the-telltaleboard which in the -form Iillustrated'"is a line-lamp,vis connected in theV circuit 'including a contact 75 incorporated inAand controlled vby thefoperation of the mainack 42),-soasto be 'closedwhen the plug visins'er'ted insai-d -jackll One side of this switch isgrounded as shown' and rthe otfhe'r'side is connectedr through theswitch 26-fonthe` remote control board as shown in Figure 1 and 'fromthence through the signal1 lamp 17" and a Ypilot relay- 76 controlling'the' pilot lamp 77 on the remote Control board. In the 'fo-rmillustrated in Figure 2, above described, it will beobserve'd that thejack 42 is: of special yconstruction' including `the con-v tact 75.I Thetell-tale-bcard is also furnished with the-usual cord circuitsandi-operators listening equipment, similar to theequipment' on 4the'main' board 10."-

Tliuse andfoperation ofthel apparatus above described lin connectionlwith Figures 1 and 2 is as follows-:Assumingt-hatfthemai'nezchnge'board `10 is located in a large establishment,such asa hot-el,` it isprovidedy with subscribers" 'circuits-servingeach of the roomsin the hotel. This board is located in the usualposition, as, for instance, in the lobby of the hotel and served by theusual telephone operator. The tell-tale board 15 may be located adjacentthe main board 10 or at any other convenient place in the hotel buildingwhere space is available. T he remote control switchboard 25 ispreferably located at the main clerks desk or a special clerks desk,where it is readily accessible to such hotel guests as may desire toavail themselves of the tell-tale service.

If the occupant of the room served by the subscribers circuitrepresented by jack 11 i and line lamp 12 on the main board 1() is inhisrooin anda call is received by the main switchboard operator, thelatter plugs in on this subscribers circuit and the bell rings in theguests room in the usual manner. If the switch 26 on the remote controlswitchboard 25 is open, the line lamp 17 corresponding to this guestsroom on the tell tale board is dead, so that no action as to thissubscribers circuit is required of the tell-tale operator. However, ifthe occupant of the room wishes to leave his room to go some other placein the hotel or to leave the hotel, he phones, or goes to the clerk orother person at the remote control switchboard and advises him of hisplans, either verbally or by leaving a written statement. Further, if hewishes to leave any message lfjora party calling him in his absence, hemay make such a statement or write the message accordingly. The remotecontrol operator then closes the switch 26 corresponding to this guestsroom number and sends the guests message to the tell tale operator atthe tell-tale board 15, either by telephone or by messenger. When theswitch 26 is closed it is obvious that any call received on t-he mainswitchboard 10 directed to this guests room will be plugged in by themain operator and the telephone in the guests room will ring in theusual manner. At the same time, however, since the circuit through thesignal line 18 is closed at switch 26, the line lamp circuit on thetell-tale board l will be energized so as to fla-sh the line signal to17 on the latter board to tell the tell-tale operator. She will thenplug in with her cord circuit and listening key in the usual manner andtalk with the calling party, advising this party of any messages whichhave been left by the labsent party if called, and to take any messageswhich the callingfparty may wish to leave. It will be observed that thesignal to t-he tell-tale opera-tor is accomplished without interruptingin any manner with the usual operation of the main switchboa-rd by itsoperator, since she plugs in and rings the subscribers room in the usualroutine manner, but the call is answered by the tell-tale operatorinstead of by the subscriber. Vshen the tell-tale operator answers thecall her cord circuit completes the talking circuit line. Therefore, inmy improved system the operation of the tell-tale board and switchmechanism is entirely independent of the operation of the mainswitchboard 10 and relieves the operator of the switchboard fromanswering for the guest after the guest fails to reply, and furthermore,saves the calling party the long wait to ascertain whether or not theguest is going to answer his phone. In fact, the tell-tale systemimmediately places the calling party in contact with the tell-taleoperator who is in a position to give him the proper information in theshortest possible time. Many other advantages will be hereinafterdescribed in greater detail.

lVhile the above example of the operation of my improved apparatus isdescribed in connection with Vthe operation of hotel switchboards itwill be understood that the apparatus is adapted to any form oftelephone service embodying a switchboard serving a` plurality of singleor multi-party subscriber lines.

ln the form shown in Figure 3, an arrangement of parts is shown similarto that in Figure 2, excepting that a standard jack of thetwo-wire typeis employed. ln this instance, the circuit for operating the signal 17on the tell-tale switchboard is vprovided sistance connected across thesubscrihers lines 40 and 41 and adapted to be actuated in the bellringing current in the s ubscribers circuit so as to close the contact81 of the relay to complete the circuit through the line lamp 17whenever the subscribers bell ringing current is applied from the cordcircuit by the operator'at the main switchboard 10.

Figure 4 is a view similar to Figure 3, but in which the Contact of theline lamp 17 on the telltale vboard is controlled through alo-wresistance relay 82 in series with one of the conductor wires such aswire 40 of the subscribers circuit and also actuated by the bell-ringingcurrent from the operators cord circuit on the main switchboard 10.

Referring now to the ferm shown inrFigy ures 5 and 6 in which the remotecontrol',

CAD

in Figures' 2,l 3, or 4, excepting that the switch 87 in line 18il isplaced directly on the tell-tale switchboard 15 instead of in anintermediate position. In the form shownv in Figure 6 the switch 87consists of a single Contact type having a spring 85, normally out' orengagement with an anvil 86 but which may be depressed by the turning ofa suitable switchley oi! the-usual ft'orm.v

My invention may also be applied in modified form directly to the mainexchange switchboard, so that the regular switchboard operator may givetell-tale service in addition to her regular duties in controlling theboard. Obviously this type of service does not present all theadvantages obtained where a separate tell-tale board is provided torelieve theregular operator of all den tails ol' telltale service. Adouble duty board 90 as shown in Figure 7 may, however, be used inconnection with a relatively small switchboard receiving such a smallnumber of calls that the regular operator will have time to attend tothe tell-tale service. In 'this u instance, my invention consists inproviding a means of selectively setting the subscribers lines by meansof a manual switch so asto automatically inform` the regular operatorthat the particular line is set :tor tell-tale service. y

In the form ci board shownfin Figure 7 a small'switch board 91`is addedat one side of lthe main board, this small board being provided with aplurality of tell-tale switches 92 each connected with the .usualsubscribers circuitv on the main board, including jaclr 93 and'signal94. A typical circuitfor this arrangement'is shown in Figure 8. Thisform oi board differs from the simple combination oi, a toll-tale switchboard 15vand main board 10 and shown in Figure 5, in that the usualtell-tale jack in multiplo with thesubscribers circuit may beeliminated, as well as the line lamp 17a in the tell tale circuit. Theseparate tell-tale acl; may be eliminated entirely since the signaloperator can use her cord circuit for talking with the calling party.The tell tale signal 17a which in the form Vshown in Figures 1 and 5 isflashed on the n separate board, may be substituted by a signaloperative on the main board in connection with the called circuitsignal. Such an arrangement is shown in detail in Figure 8 in which thesubscribers circuit and plug are of the usual torni, but in addition,the telltale switch 92 is provided on the board 93 in circuit with anaudibletell-tale signal 95 in parallel wit the subscribers circuitthrough conductors 96 and 97,-so that when the switch 92 is closed, thetell-tale-signal is operated by the ringingcurrent applied by theoperator in the usual manner through her cord circuit. With thisarrangement, whenever the op# era-tor inserts her calling plug in asubscribers jack the ltell-talecircuit of which has previ-v ously beenclosed by its respective tell-taleswitch 92, she will be automaticallyadvised of the fact that this particular line has been set for tell-taleservice by the ringing of the audible signal 95 when she rings thesubscribers station in the usual way. This diagram also shows anothermeans of signalling the operator for tell-tale service, comprising aconductor 97 and relay 98 for roperating another relay circuitcontrolling the usual line signal 17. AThis line signal 17 is providedwith the usual calling relay 54, arranged to disconnect the line signalwhen the operator plugs in on the subscribers jack. In the present form,however, the circuit controlled by the relay 98 and actuated by the bellringing current passes through conductors 99, 100 and 101 to light theline signal 17 whenever the tell-tale switch 92 is closed. In thismanner the operator gets the flash of the lamp 17 to indicate that theparticular subscribers telltale switch has been set. Obviously., theaudible signal 95 and the line signal 17 may be used, either inconjunction with each other,

or maybe use-d separately, if desired. For eX- ample, Figure 9 shows asimplilied arrangement in which the relayfor actuating the line lampbythe bell ringingcurrent is omitted.

Figure 10 is a view illustrating the mane ner in which asingle-tell-tale signal yon the double duty switchboard may beused toserve a'plurality `of s ubscribers lines, each:

, comprising conductors 40 and 41.' One side or" said subscribers lines,such as conductors 40 are each connected to one of the tell-tale switchlines 18, 18, leading to` one side of separate tell-tale switches 92,92, the other side of 'said switches having common connection throughsignal and conductor 105 to the other conductor 41 of all of thesubscribers lines. In this manner a single audible signal may be used toserve all of the'subscribers stations on a double duty switchboard asillustrated in Figures 7, 8 and 9. i

In vthe form shown in Figure 11, the telltalev` switch is incorporateddirectly upon the doubleduty board. The "subscribers jack shown in thislfigure is provided with the usual line signal 17 and line signal relay54 operative so that the line signal flashes when the subscriber iscalling, but is discontinued in the usual manner, as soon as theoperator inserts her answering pluo. In addition to this equipment, Iprovide a tell-tale signal circuit, includinga tell-tale switch contact109 which is depressed, when closed, so that when the calling plug isinserted in the subscribers jack, another circuit is completed throughthe line signal 17, traced as follows: line battery 55, line signal 17,anvil 111, contact 109, conductor 112, anvil 113, jack contact 114, andground line 115, so as to cause the line signal 17 to continue to burnafter the calling plug is inserted in the jack.

trolled to complete a circuit through the operators cord circuit plug111 and circuit 112 direct to ground through a grounded cut-off 113, orthrough the tell-tale line signal 17". This arrangement may be appliedeither to a separate tell-tale board system or to a double-duty board.In the latter instance it may be convenientto providek an operatorssignal in the cord circuit, by means of a lamp 115 which may be one ofthe usual through-circuit-signals added to the cord circuit. If desired,the tell-tale line 18a may also be provided with an operating relay 116and line battery 117, as shown in Figure 13. I

From the above description of several simpliiied arrangements forproducing thetelltale signal and answering circuits, it will be manifestthat many other modifications of my invention will readily suggestthemselves to anyone skilled in the art. I do not therefore wish to beunderstood to be limited to the exact constructions shown and described,excepting as defined in the following claims.

I claim:

1. A telephone system comprising an exchange switchboard provided with aplurality of separate circuits for individual subscribers, and eachhaving an answering jack, a cord circuit including a calling apparatusfor said subscribers circuits, and trunk lines therefor, and anauxiliary circuit including an independent control device and a signalconnected with each of said subscribers circuits, whereby the signal isautomatically actuated by the calling apparatus effective in each of thesubscribers circuits when the corresponding control device is set in apredetermined position, and an answering jack adjacent said auxiliarysignal and in parallel with the corresponding answering jack on theexchange switchboard.

2. A telephone system comprising an exchange switchboard provided with aplurality of separate circuits for individual subscribers, and eachhaving an answering jack, a cord circuit including a calling apparatusfor said subscribers circuits, and trunk lines therefor, and anauxiliary circuit including an independent control device and a signalconnected with each of said subscribers circuits and adapted to beautomatically actuated by the calling apparatus effective in each of thesubscribers circuits when the corresponding control device is set in apredetermined position, and an auxiliary answering jack adjacent each ofsaid auxiliary signals and in parallel with the corresponding answeringjacks In this instance, the Y on the switchboard, said auxiliaryanswering jacks and signals being mounted on a board separate from themain switchboard.

3. A. telephone system comprising an exchange switchboard equipmentincluding a plurality of subscribers circuits each having an answeringjack, and calling apparatus therefor, and an auxiliary circuit includinga control device rand a signal connected Lwith each of said subscriberscircuits and adapted to be automatically' actuated by the callingapparatus eifective in each of the subscribers circuits when thecorresponding control device is set in a predetermined position, and anauxiliary jack adjacent each ofl said auxiliary signals and in parallelwith the corresponding answering jack on the switchboard,

said auxiliary answering jacks and signals being mounted on a boardseparate from the main switchboard, and the control devices beinginterposed in a separate group between the main switchboard and theauxiliary switchboard.

4. A telephone system comprising an exchange switchboard equipmentincluding a plurality of subscribers circuits each having an answeringjack, and calling apparatus therefor, and an auxiliary circuit includinga manual switch and a signal connected with each of said subscriberscircuits and adapted to be automatically actuated by the callingapparatus effective in each of the subscribers circuits when thecorresponding manual switch is in closed position, and an auxiliary ianswering jack adjacent each of said aux- -iliary signals and inparallel with the corresponding answering jack on the switchboard, saidauxiliary answering jacks and signals being mounted on a board separatefrom the Y main switchboard, and the manual switch devices beinginterposed in a separate group between the main switchboard andthe aux'-iliary switchboard.

5. An oliice building telephone service system, comprising an incomingtelephone line, a telephone set connected thereto in a tenants oii'ice,a line from said telephone set to an outlet in a central switchboard,identifying means adjacent said outlet, and switch means operable fromsaid tenants office to route an incoming call directly to the centralswitchboard, or to the telephone set in the office of the tenant, atwill.

Signed at Chicago, February, 1925.

LESTER J. STEVENSON.

in., this istil day of

